[Maximum number: 1]

This question is about states of matter.

A solution is a mixture of a solute and a solvent.

Name the process when a solid substance mixes with a solvent to form a solution.

[Maximum number: 1]

A student separates sugar from pieces of broken glass by dissolving the sugar in water and filtering off the broken glass.

What is the filtrate?

A

broken glass only

B

broken glass and sugar solution

C

pure water

D

sugar solution

[Maximum number: 1]

A student separates sugar from pieces of broken glass by dissolving the sugar in water and filtering off the broken glass.

What is the filtrate?

A

broken glass only

B

broken glass and sugar solution

C

pure water

D

sugar solution

[Maximum number: 1]

A student separates sugar from pieces of broken glass by dissolving the sugar in water and filtering off the broken glass.

What is the filtrate?

A

broken glass only

B

broken glass and sugar solution

C

pure water

D

sugar solution

[Maximum number: 2]

Calcium hydroxide, $\mathrm{Ca}(\mathrm{OH})_{2}$ , is slightly soluble in water.

Limewater is a saturated solution of calcium hydroxide, $\mathrm{Ca}(\mathrm{OH})_{2}(\mathrm{aq})$ .

Suggest what is meant by the term saturated solution.

[Maximum number: 2]

Soluble salts can be made by adding a metal carbonate to a dilute acid.

A student wanted to make hydrated iron(II) sulfate crystals, $\mathrm{FeSO}_{4} \cdot x \mathrm{H}_{2} \mathrm{O}$ , by adding excess iron(II) carbonate to dilute sulfuric acid. The student followed the procedure shown.
step 1 Add dilute sulfuric acid to a beaker.
step 2 Add small amounts of iron(II) carbonate to the dilute sulfuric acid in the beaker until the iron(II) carbonate is in excess.
step 3 Filter the mixture formed in step 2.
step 4 Heat the filtrate until it is a saturated solution. Allow to cool.
step 5 Once cold, pour away the remaining solution. Dry the crystals between filter papers.

A saturated solution is formed in step 4.

Describe what a saturated solution is.

[Maximum number: 2]

Magnesium sulfate and lead(II) sulfate are examples of salts.

A student prepared magnesium sulfate crystals starting from magnesium carbonate. The student carried out the experiment in four steps.
step1 The student added excess magnesium carbonate to a small volume of dilute sulfuric acid until no more magnesium carbonate would react.
step 2 The student filtered the mixture.
step 3 The student heated the filtrate obtained from step 2 until it was saturated.
step 4 The student allowed the hot filtrate to cool to room temperature and then removed the crystals which formed.

A saturated solution forms in step 3.

What is a saturated solution?

[Maximum number: 2]

Sulfur is an important element.

Dilute sulfuric acid is used to make salts known as sulfates.

A method consisting of three steps is used to make zinc sulfate from zinc carbonate.
step 1 Add an excess of zinc carbonate to $20 \mathrm{~cm}^{3}$ of $0.4 \mathrm{~mol} / \mathrm{dm}^{3}$ dilute sulfuric acid until the reaction is complete.
step 2 Filter the mixture.
step 3 Heat the filtrate until a saturated solution forms and then allow it to crystallise.

What is meant by the term saturated solution in step 3?

[Maximum number: 3]

Zinc is manufactured from zinc blende. Zinc blende is an ore which consists mainly of zinc sulfide, ZnS .

(a)

Zinc reacts with dilute sulfuric acid to produce aqueous zinc sulfate.

\mathrm{Zn}(\mathrm{~s})+\mathrm{H}_{2} \mathrm{SO}_{4}(\mathrm{aq}) \rightarrow \mathrm{ZnSO}_{4}(\mathrm{aq})+\mathrm{H}_{2}(\mathrm{~g})

Hydrated zinc sulfate crystals are made from aqueous zinc sulfate.
Step 1 Solid zinc is added to dilute sulfuric acid until zinc is in excess.
Step 2 Excess zinc is separated from aqueous zinc sulfate by filtration.
Step 3 Aqueous zinc sulfate is heated until the solution is saturated.

Step 4 The saturated solution is allowed to cool and crystallise.
Step 5 The crystals are removed and dried.

[ 3 ]

(i)

Name the residue in step 2 .

[ 1 ]

(ii)

In step 3, a saturated solution is produced.

Describe what a saturated solution is.

[ 2 ]

[Maximum number: 2]

Sulfuric acid has many uses.

Dilute sulfuric acid is used to make salts known as sulfates.

A method consisting of three steps is used to make zinc sulfate from zinc carbonate.
step 1 Add an excess of zinc carbonate to $20 \mathrm{~cm}^{3}$ of $0.4 \mathrm{~mol} / \mathrm{dm}^{3}$ dilute sulfuric acid until the reaction is complete.
step 2 Filter the mixture.
step 3 Heat the filtrate until a saturated solution forms and then allow it to crystallise.

Define the term saturated solution.

Question 1(d)(i)

Question 3

Question 3

Question 3

Question 2(c)(ii)

Question 2(b)(iv)

Question 3(a)(iii)

Question 3(c)(iv)

Question 4

Question 4(c)

Question 4(c)(i)

Question 4(c)(ii)

Question 4(b)(iii)